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U.S.  DEPARTMBWP^PF  AGRICULTURE 
BUREAU   OF   BHT0M0L0O1     CIRCULAR   No.  166. 

L.  O.   HOWARD.    I  ntomolosisl  anil  (  lurl  ,.(  Iiuir»u. 


FLOUR  PASTE  IS  \  CONTROL  FOR  RED  SPIDERS 


\\1> 


AS  \  SPREADER  FOR  CONTACT  INSECTICIDES. 


WILLIAM  B.   PARKER 


vt 


BUREAU   OF  EXTOMOLOGY. 

L.  O.  Howard.  Entomologist  and  Chief  of  Hunan. 

C.  L.  Mari.att.  Entomologist  and  Acting  Chief  in  Absence  of  Chief. 

R.  S.  Clifton.  Executive    Issistant. 

W.  F.  Tastet.  Chief  Clerk. 

F.  H.  Chittenden,  in  charge  of  truckorop  and  stored  product  insect  investigations, 

A.  D.  Hopkins,  in  charge  of  forest  insect  investigations. 

W.  D.  HtrNTEB,  in  charge  of  southern  field  crop  insect  investigations. 

F.  M.  Webster,  in  charge  of  cereal  and  forage  insect  investigations. 

A.  L.  Quaintance.  in  charge  of  deciduous  fruit  insect  investigations. 

E.  F.  Phillips,  in  charge  of  bee  culture. 

I).  M.  Rogers,  in  charge  of  preventing  spread  of  moths,  petit  work. 

Rolla  P.  Cubbie,  in  charge  of  editorial  work. 

Mabel  Colcord.  in  charge  of  library. 

Truck  Crop  and  Stored  Product  Insect  Investigations. 
F.  H.  Chittenden,  in  charge. 

C.  H.  Popenoe,  William  P».  Parker.  H.  O.  Marsh.  M.  M.  High,  Fred  A.  John- 
ston, John  E.  Graf.  C.  F.  Stahl,  D.  E.  Fink,  entomological  assistants. 
A.  B.  Duckett,  scientific  assistant. 
I.  J.  Condit,  collaborator  in  California. 
W.  N.  Ord,  collaborator  in  Oregon. 
Thomas  H.  Jones,  collaborator  in  Porto  Rico. 
Marion  T.  Van  Horn.  Pauline  M.  Johnson.  Anita  M.  P.allinger.  preparators, 

ii 


Circular  r\ 


United  States  Department  of  Agriculture, 

BUREAU  OK  ENTOMOLOGY. 

L.   O.   IIOWAKD.    Bntomolc    i»l    ."■!   Chief  of   Uuir 


FLOUR   PASTE  As  A   CONTROL   FOB   RED  SPIDERS    \\l> 
As   A   SPREADEB    FOB  CONTACT   [NSECTICIDE8. 


Bj    H  ill  hm     I'.     I'm: 

Entomali  >•!•  til    i  -.-i^in ill . 
1:1  -i  i  h  i  'i    i  \ri  i;i  mi  STS. 


I  > 1 1 1 ■  1 1 1 i_r  some  spraj  ing  experiments  for  the  control  i  f  the  red  spider 
(Tetranychws  bimacvlatus  Harv.)  on  hops  in  L912  some  difficulty  was 


w 

p*l  t 

i^^^     111 

il 

H 

F        *^     '  VI 

1 

I 

J 

■^^^y 

^H 

i 

Ki'..   1  .—Lime  •sulphur  mixture  and  Door  paste    ii.fr   half),  Bhowii  - 

flour  paste;   lime-sulphur  mixture  straight    (right  balf),  Bhowing  due  to 

lack  of  Dour  paste     (Original.) 

experienced  in  obtaining  an  effective  spreader  for  the  lime-sulphur 
solutions,  due  to  the  fact  that  soap  forms  a  precipitate  with  the  cal- 
cium polysulphid.     While  testing  the  following  combination — flow- 

l 


2  I  I. oil;    PASTE   AS   A   CONTROL   FOR    RED   SPIDERS. 

crs  of  sulphur  15  pounds,  water  LOO  gallons,  and  Hour  paste  (as  a 
"sticker")  4  gallons — a  formula  advised  for  red  spiders  in  Bulletin 
NO.  154  by  Mr.  W.  II.  Voids  of  the  California  Experiment  Station, 
it  was  observed  that  the  mixture  spread  over  the  leaves  very  readily. 
The  Hour  paste  was  evidently  the  spreader  and  was  accordingly 
mixed  with  the  lime-sulphur  solutions.  The  result  was  a  smooth 
mixture  which  spread  over  the  foliage  very  readily  and  gave  unusual 
results  as  an  arachnicide.  The  proper  proportions  were  found  to  be 
4  gallons  of  paste  (4  pounds  of  Hour)  to  100  gallons  of  spray.  Table 
I  graphically  represents  the  relative  effectiveness  of  the  lime-sulphur 
spray,  with  and  without  the  flour  paste,  for  the  red  spider  on  hops. 

Table  I. — Relative  effectiveness  of  lime-sulphur  spray,  with  and  without  flow 
paste,  against  the  red  spider,  on  hops  in  the  Sacramento  Valley  of  California, 

in  mi.'. 


Formula. 


Number  Number 
of  mites  of  mites 
present.      killed. 


Per  cent 

of  mites 
killed. 


Lime-sulphur,  36°  Baumi'>,  1-75;  flour  paste,  4-100. 
Lime-sulphur,  36°  Baume,  1-75 


698 
300 


092 
135 


99.0 
37.5 


From  the  foregoing  table  it  is  very  evident  that  the  use  of  flour 
paste  greatly  increases  the  efficiency  of  the  lime-sulphur  spray  and 
that  without  the  paste  the  spray  was  very  ineffective.  These  results 
were  substantiated  by  other  experiments  and.  by  a  check  experiment 
with  the  flour  paste.  4-100.  used  without  the  lime-sulphur,  it  was 
found  that  the  increased  efficiency  was  mainly  due  to  the  spreading 
effect  of  the  paste. 

Having  proved  a  most  efficient,  cheap,  and  convenient  spreader  for 
the  lime-sulphur  solutions,  some  experiments  were  conducted  with 
flour  paste  in  combination  with  nicotine  sulphate  upon  the  hop  aphis 
(Phorodon  humuli  Schrank).     (See  Table  II.) 

Table  II. — Results  obtained  by  spraying  with  combinations  of  flour  paste  and 
nicotine  sulphate  in  different  proportions  against  the  hop  aphis,  Sacramento 
Valley  of  California.   1912. 


Formula. 


Number 
of  aphides 
1  present 


Aphides 
killed. 


Cost  per 

100 
gallons. 


Nicol  ine  sulphate.  1-2.000:  flour  paste,  4-100 027 

Nicotine  sulphate,  1-2.500;  flour  paste.  4-100 611 

Nicotine  sulphate.  1  3.000;  flour  paste,  4-100 

Nicotine  sulphate.  1  3,000;  flour  paste,  4-100 148 


Pit  ant. 
100 
100 
99 
99 


Cents. 

0.71 

.60 

.50 

.50 


From  the  preceding  table  it  is  very  evident  that  Hour  paste,  4-100, 
is  a  very  effective  spreader  for  nicotine  sulphate. 

The  efficiency  of  Hour  paste  as  a  spreader  was  very  evident  to  the 
writer,  but  it  was  deemed  advisable  thorough!}'  to  illustrate  this  point. 


I'l  OUR    PASTI      VS    \    i  u\  i  Ri  »i      i  OH    RED    SI'IDKRS. 


3 


Two  hopvines  were  accordingly  sprayed,  one  with  lime-sulphur 
straight  nnd  the  other  with  lime-sulphur  and  flour  paste,  t-100. 
The  relative  spreading  effecl  of  these  two  sprays  i-  shown  in  tiu 
ore  l.  The  left  half  of  the  figure  represents  the  lime-sulphur  and 
the  flour  paste  in  combination,  while  tin'  right  half  represents  the 
lime-sulphur  straight.  The  spotted  effect  produced  l>y  the  lime- 
Bulphur  mixture  alone  is  in  strong  contrast  i<>  the  even  appearance 
of  the  other  half  of  i  In*  illustration. 

During  some  spraying  experiments  with  nicotine  sulphate  and 
flour  paste  upon  the  hop  aphis  it  was  observed  thai  many  <>f  the 
smaller  aphides  had  become  pasted  onto  the  leaves.  From  this  data 
it  was  assumed  that  ;i  stronger  solution  of  paste  would  be  effective 
against  the  more  delicate  aphides  and  mites,  and  the  following 
experiments  were  conducted  upon  the  red  spider. 

Tabu    III.     Results  of  i  rperimentt  with   flour  past*    ipraycd  againti  tin    red 

tpider  "»  ho/is  in  /in    sni niiiii  nin   I  nth  a  ni  California,   1912. 


Formula 

N  amber 
of  mites 

killed. 

Coal  [ht 

100 
gallons. 

June   1>> 
June  :>7 

Flour  paste,  8  100. 
do 

7M 

152 
177 

Per  crnl. 
100 
N  8 

100 

17  6 

17  8 

Jul  v    13 

r  8 

do 

17  8 

.do 

17 .  r, 

17  8 

total  I'uimt 

av.t  ige 

Flour  pasio.  10  1  ■  m > 

3,759 

99.9 

Julv    16 

805 
908 

99.9 
99.9 

22 

Aiilv     8 

do 

22 

1,712 

99.9 

These  experiments  prove  that  Hour  paste,  8  LOO  and  10-100.  is 
effective  against  Tetrany chits  bimaeulatus.  The  paste  has  no  effect 
upon  the  i'ir.i.r>.  however,  and  in  controlling  the  mites  a  second 
application  7  to  1<>  days  after  the  firsl  is  necessary  to  catch  the  mites 
that  emerge  from  the  eggs, 

A  few  preliminary  experiments  were  conducted  with  this  material 
upon  Tetranychus  mytilaspidis  Riley  which  was  attacking  pears,  with 
verj  encouraging  results,  and  it  is  very  probable  that  flour  paste, 
8-100,  will  give  good  results  when  applied  for  any  of  the  small  leaf- 
feeding  mites. 

The  last  of  June,  1912,  flour  paste,  s  100,  was  applied  for  the  hop 
aphis  (then  in  the  younger  stages)  with  a  97  per  cent  efficiency. 
These  were  encouraging  results,  bul   later  experiment-  proved  that. 

'in  moderate  weather  allow   10  days  and   In   bot   weather  7  days  between 

•implications. 


-i  FLOUR   PASTE   AS   A    CONTROL   EOR    RED   SPIDERS. 

although  the  solution  was  effective  against  some  very  delicate  species 
and  the  younger  stages  of  the  hop  aphis,  it  was  not  effective  against 
the  stouter  aphides. 

When  the  paste  was  dry  the  mites  and  more  delicate  aphides 
treated  were  found  firmly  pasted  onto  the  leaves.  Later  the  paste 
film  was  observed  to  crack  and  partially  scale  off.  leaving  the  leaf 
free  to  perform  its  natural  functions. 

The  neutrality  of  this  spray  was  proved  by  the  fact  that  when 
applied  upon  the  foliage  and  blossoms  of  the  hop  in  proportions  as 
high  as  12  pounds  to  100  gallons  no  injurious  effect  resulted. 
"W  hen  sprayed  onto  the  burrs  and  delicate  hop  cones  it  did  not  pre- 
vent pollination  or  injure  the  appearance  of  the  scales. 

Flour  paste  has  proved  effective  when  applied  for  red  spiders  upon 
the  following  plants: 


Beans. 

Chrysanthemum    (may   spot   leaves 
used  too  near  blossoming  time). 

HcipS. 

Cucumber,  greenhouse  and  field. 


Pumpkin. 

Pea  r. 

Prune. 

Poses  in  field. 

Violets,  field  and  greenhouse. 


The  Hour  paste  was  not  satisfactory  when  used  for  the  red  spider 
on  greenhouse  roses  (did  not  spread  well),  greenhouse  carnations,  or 
field  sweet  peas. 

PREPARATION  OF  PASTE. 

To  prepare  the  flour  paste,  mix  a  cheap  grade  of  wheat  flour  with 
cold  water,  making  a  thin  batter,  without  lumps:  or  wash  the  flour 
through  a  wire  screen  with  a  stream  of  cold  water.  Dilute  until  there 
is  1  pound  of  flour  in  each  gallon  of  mixture.  Cook  until  a  paste  is 
formed,  stirring  constantly  to  prevent  caking  or  burning.  Add  suffi- 
cient water  to  make  up  for  evaporation. 

Flour  paste  may  also  be  prepared  by  stirring  boiling  water  into 
a  moderately  thin  batter  until  there  is  1  pound  of  flour  in  each 
gallon  of  mixture  and  allowing  it  to  stand  until  the  starch  is  all 
broken  down. 

If  the  paste  is  not  sufficiently  cooked,  the  resulting  spray  will  not 
be  effective,  and  if  overcooked  the  paste  will  harden  when  thor- 
oughly cool,  and  will  not  mix  with  water  very  readily.  Usually, 
however,  the  paste  is  used  as  it  is  prepared,  and  overcooking  is  not 
a  disadvantage. 

When  mixed  in  the  spray  tank  flour  paste  has  a  tendency  to  settle, 
and  in  order  to  do  satisfactory  work  agitation  is  necessary.  This 
is  but  a  slight  disadvantage,  and  is  necessary  with  most  materials. 

Flour  paste  appears  to  be  a  very  effective  spreader  for  lime-sul- 
phur and   nicotine-sulphate  sprays.     Cheap  flour  can  be  purchased 


I  I  111   i;    PASTE    \-    \    CONTROI     POB    BED   SPIDI  RS.  D 

for  less  1 1 1 ;i n  half  the  cost  of  whale-oil  Boap.     It   is  always  obtain 

able,  and  having  i dor  it   i-  less  offensive  to  use  than  the  whale 

oil  and  fish-oil  -<>;i|i~.  Winn  used  alone  it  ili<-  rate  of  v  gallons  iv 
|)(iiiinl-  flour)  to  100  gallons  of  water  it  is  effective  against  several 
leaf  feeding  mites  and  some  verj  delicate  aphides.    The  possibility 


Fig. 2. —  Hindu  making  Dour  paste,  Sacramento  Valley,  Cal.,  1 ; •  1  - .     (Original.) 

of  it-  use  as  a  spreader  for  lime-sulphur  sprays  for  scale  insects  and 
fungi  and  a>  a  "sticker"  for  arse nicals  has  not  yet  been  worked  out, 
but  from  observations  during  the  past  four  months  it  is  believed  tbat 
it  may  have  some  value  along  these  lines. 
Approved : 

James  Wilson, 

§  of  A  <n  '"  ultui  <  . 

Washington,  I  >.  C,  November  .'■>'.  1912. 


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ent  of'  Documents,   Government    Printing 
Oii'.ce,  Washington .  I> .  <  r  oopy 


UNIVERSITY  OF  FLORIDA 

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3  1262  09216  5777 


